By Casey Bennett, Director of Fire Technologies
The number of fires in warehouses has decreased precipitously since a peak of roughly 4,700 per year in 1980, but today warehouse fires are more dangerous, and more expensive.
According to research from the National Fire Protection Association, from 2020-24 an average of approximately 1,500 annual warehouse fires resulted in two civilian deaths, 17 injuries and over $300 million in property damage per year.
In that same timeframe, warehouse construction has also changed. The average warehouse facility in the United States is roughly 17,000 square feet, but the average warehouse built in the last five years is almost 200,000 square feet.
Modern facilities are larger, more complex, and house more expensive, flammable commodities than ever before.
Big Box Warehouses
Warehouses have always been fire risks, but at the size and complexity they are being constructed with today, those risks have compounded.
The fire detection and suppression systems installed in these facilities are more important than ever, with specialized sprinkler systems, 24/7 monitoring and radio amplification systems.
Many of these massive distribution centers also include large rack systems that make up their own structures with automated storage and retrieval systems that complicate the risk profile.
Fire Detection
Fire detection on these facilities must be robust, as racks and shelving can obscure the signs of ignition for longer while fire burn.
Heat and smoke detectors should be deployed facility-wide, and depending on local ordinances, additional measures may be needed.
Notifier Inspire series fire alarm control panels from Honeywell are addressable and can manage up to 3,180 devices on a network of up to 200 nodes, allowing for a potential of 63,600 addressable points.
Not only does this make routine maintenance and inspections easier but it can provide first responders with vital information during an emergency, like the location of a fire and how many devices have been activated.
Very Early Warning Detection Apparatus (VESDA) systems are some of the most sensitive smoke detection systems available. Produced by Honeywell, they can detect smoke particles in concentrations as low as 0.005% obscuration per meter.
Fire Suppression
Most large warehouses will need extensive sprinkler systems to give firefighters time to respond in the event of a fire. Sprinkler systems will affect the warehouse’s capacity and construction with requirements for proximity to racks.
Traditional sprinkler systems can release water at a rate of 10-20 gallons per minute.
In applications like these, traditional systems are insufficient and will not disperse enough water to contain the spread of fire through racks of flammable commodities.
Instead, Early Suppression Fast Response (ESFR) sprinkler systems are used; they are much more sensitive to heat and can release a mind-boggling 100 gallons of water per minute.
These systems also significantly increase the device count at these facilities as many jurisdictions require these systems at each level of shelving throughout the building.
On top of these requirements, cold storage warehouses have their own constraints.
Cold Storage Warehouses
Cold storage warehouses are also becoming increasingly common. They are used to store perishable food products and medications at cold, or even freezing temperatures.
The growth of these facilities has been drive by convenience services like grocery delivery and frozen meal prep subscription services, in addition to the increase in medications requiring cold storage.
These facilities are not without their own risks, and last month a cold storage facility the size of a city block in Los Angeles caught fire, and burned for six straight days.
Cold storage frequently uses a “box-in-box” construction in which a smaller portion of the building will be refrigerated or will maintain a freezing temperature. The complex layout of these structures can be hazardous for first responders.
These issues are only multiplied as the polyurethane insulation used to maintain below-freezing temperatures is flammable and produces large quantities of opaque smoke when ignited.
Pre-action sprinkler systems are used to prevent water from freezing in pipes. They are instead filled with compressed air in cold and freezing areas with valves that release water into the pipes when sprinklers are activated.
Communcations
The sheer size of these facilities and the intricate shelving apparatus also create communication issues, and Emergency Responder Communications Enhancement Systems (ERCES) can be mandated by the Authority Having Jurisdiction.
These systems use bi-directional amplifiers to strengthen radio communications inside the building by redirecting frequencies from nearby radio towers to the amplifiers within the building using a donor antenna on the roof.
For more information on how to keep trucks moving in and out of your facility, and how to keep your inventory safe, schedule a consultation.
